SPDR Series Trust

SPDR^® Portfolio Intermediate Term Treasury ETF

SPTI

(NYSE Ticker)

(formerly, SPDR Bloomberg Barclays Intermediate Term Treasury ETF)

Summary Prospectus-October 31, 2018
(As Revised September 23, 2019)

Before you invest in the SPDR^® Portfolio Intermediate Term Treasury ETF (formerly, SPDR Bloomberg Barclays Intermediate Term Treasury ETF) (the “Fund”), you may want to review the Fund's prospectus and statement of additional information, which contain more information about the Fund and the risks of investing in the Fund. The Fund's prospectus and statement of additional information dated October 31, 2018, are incorporated by reference into this summary prospectus. You can find the Fund's prospectus and statement of additional information, as well as other information about the Fund, online at https://www.spdrs.com/product/fund.seam?ticker=SPTI.

You may also obtain this information at no charge by calling 1-866-787-2257 or by sending an e-mail request to Fund_inquiry@ssga.com.

Investment Objective

The SPDR Portfolio Intermediate Term Treasury ETF (the “Fund”) seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the intermediate-term sector of the United States Treasury market.

Fees and Expenses of the Fund

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund (“Fund Shares”). This table and the Example below reflect the expenses of the Fund and do not reflect brokerage commissions you may pay on purchases and sales of Fund Shares.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):

Management fees¹	0.06%
Distribution and service (12b-1) fees	None
Other expenses	0.00%
Total annual Fund operating expenses¹	0.06%

¹	The Fund's “Management fees” and “Total annual Fund operating expenses” have been restated to reflect a reduction in the Fund's “Management fees.”

Example:

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell all of your Fund Shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Year 1	Year 3	Year 5	Year 10
$6	$19	$34	$77

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 61% of the average value of its portfolio.

The Fund's Principal Investment Strategy

In seeking to track the performance of the Bloomberg Barclays 3-10 Year U.S. Treasury Index (the “Index”), the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk

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and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA Funds Management, Inc. (“SSGA FM” or the “Adviser”), the investment adviser to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective.

Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index or in securities that the Adviser determines have economic characteristics that are substantially identical to the economic characteristics of the securities that comprise the Index. In addition, in seeking to track the Index, the Fund may invest in debt securities that are not included in the Index, cash and cash equivalents or money market instruments, such as repurchase agreements and money market funds (including money market funds advised by the Adviser).

The Index is designed to measure the performance of intermediate term (3-10 years) public obligations of the U.S. Treasury. The Index includes all publicly issued U.S. Treasury securities that have a remaining maturity of greater than or equal to 3 years and less than 10 years, are rated investment grade and have $300 million or more of outstanding face value. In addition, the securities must be denominated in U.S. dollars, fixed rate and non-convertible. Securities excluded from the Index include state and local government series bonds, inflation protected public obligations of the U.S. Treasury, commonly known as “TIPS,” floating rate bonds and coupon issues that have been stripped from bonds included in the Index. The Index is market capitalization weighted and the securities in the Index are updated on the last business day of each month. As of August 31, 2018, there were approximately 113 securities in the Index, the dollar-weighted average maturity of the securities in the Index was 5.61 years and the modified adjusted duration of securities in the Index was approximately 5.16 years.

The Index is sponsored by Bloomberg Index Services Limited (the “Index Provider”), which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks of Investing in the Fund

As with all investments, there are certain risks of investing in the Fund. Fund Shares will change in value, and you could lose money by investing in the Fund. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Debt Securities Risk: The values of debt securities may increase or decrease as a result of the following: market fluctuations, increases in interest rates, actual or perceived inability or unwillingness of issuers, guarantors or liquidity providers to make scheduled principal or interest payments or illiquidity in debt securities markets; the risk of low rates of return due to reinvestment of securities during periods of falling interest rates or repayment by issuers with higher coupon or interest rates; and/or the risk of low income due to falling interest rates. To the extent that interest rates rise, certain underlying obligations may be paid off substantially slower than originally anticipated and the value of those securities may fall sharply. In recent years, the U.S. has experienced low interest rate levels. However, interest rates have begun to rise. In addition, economic recovery and the ending of the Federal Reserve Board's quantitative easing program increase the likelihood that interest rates will continue to rise in the future. A rising interest rate environment may cause the value of the Fund's fixed income securities to decrease, an adverse impact on the liquidity of the Fund's fixed income securities, and increased volatility of the fixed income markets. If the principal on a debt obligation is prepaid before expected, the prepayments of principal may have to be reinvested in obligations paying interest at lower rates. During periods of falling interest rates, the income received by the Fund may decline. Changes in interest rates will likely have a greater effect on the values of debt securities of longer durations. Returns on investments in debt securities could trail the returns on other investment options, including investments in equity securities.

Income Risk: The Fund's income may decline due to falling interest rates or other factors. Issuers of securities held by the Fund may call or redeem the securities during periods of falling interest rates, and the Fund would likely be required to reinvest in securities paying lower interest rates. If an obligation held by the Fund is prepaid, the Fund may have to reinvest the prepayment in other obligations paying income at lower rates.

Indexing Strategy/Index Tracking Risk: The Fund is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. As a result, the Fund's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index and, consequently, the performance, volatility, and risk of the Fund. When there are changes made to the component securities of the Index and the Fund in turn makes similar changes to its portfolio, any transaction costs and market exposure arising from such portfolio changes will be borne directly by the Fund and its shareholders. The Fund may recognize gains as a result of rebalancing or reconstituting its securities holdings to reflect changes in the securities included in the Index. The Fund also may be required to distribute any such

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gains to its shareholders to avoid adverse federal income tax consequences. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Fund's return may not match the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Fund may not be fully invested at times, generally as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to replicate the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Fund's return and that of the Index.

Liquidity Risk: Lack of a ready market or restrictions on resale may limit the ability of the Fund to sell a security at an advantageous time or price or at all. Illiquid securities may trade at a discount from comparable, more liquid investments and may be subject to wide fluctuations in market value. Illiquidity of the Fund's holdings may limit the ability of the Fund to obtain cash to meet redemptions on a timely basis. In addition, the Fund, due to limitations on investments in any illiquid securities and/or the difficulty in purchasing and selling such investments, may be unable to achieve its desired level of exposure to a certain market or sector.

Market Risk: The Fund's investments are subject to changes in general economic conditions, and general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors including, but not limited to, economic growth or recession, changes in interest rates, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets.

Non-Diversification Risk: As a “non-diversified” fund, the Fund may hold a smaller number of portfolio securities than many other funds. To the extent the Fund invests in a relatively small number of issuers, a decline in the market value of a particular security held by the Fund may affect its value more than if it invested in a larger number of issuers. The value of Fund Shares may be more volatile than the values of shares of more diversified funds.

Securities Lending Risk: The Fund may engage in securities lending. Securities lending involves the risk that the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money due to a decline in the value of collateral provided for loaned securities or any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund. To the extent the collateral provided or investments made with cash collateral differ from securities included in the Index, such collateral or investments may have a greater risk of loss than the securities included in the Index.

U.S. Treasury Obligations Risk: U.S. Treasury obligations may differ from other fixed income securities in their interest rates, maturities, times of issuance and other characteristics. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund's U.S. Treasury obligations to decline.

Valuation Risk: Some portfolio holdings, potentially a large portion of the Fund's investment portfolio, may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including “fair valued” securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. In addition, there is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time. Investors who purchase or redeem Fund Shares on days when the Fund is holding fair-valued investments may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund had not fair-valued the holding(s) or had used a different valuation methodology.

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Fund Performance

The following bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns for certain time periods compare with the average annual returns of the Index and another index measuring market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available by calling 1-866-787-2257 or visiting our website at https://www.spdrs.com.

Annual Total Returns (years ended 12/31)*

Highest Quarterly Return: 6.53% (Q4, 2008)
Lowest Quarterly Return: -2.28% (Q4, 2016)

*	As of 9/30/2018, the Fund's Calendar Year-To-Date return was -0.93%.

Average Annual Total Returns (for periods ended 12/31/17)

The after-tax returns presented in the table below are calculated using highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your specific tax situation and may differ from those shown below. After-tax returns are not relevant to investors who hold Fund Shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. The returns after taxes can exceed the returns before taxes due to an assumed tax benefit for a shareholder from realizing a capital loss on a sale of Fund Shares. Effective April 30, 2018, the Fund's benchmark index changed from the Bloomberg Barclays Intermediate U.S. Treasury Index to the Bloomberg Barclays 3-10 Year U.S. Treasury Index, consistent with a change in the Fund's principal investment strategy to track the performance of the new index.

	One Year	Five Years	Ten Years
Return Before Taxes	1.05%	0.81%	2.67%
Return After Taxes on Distributions	0.41%	0.26%	1.98%
Return After Taxes on Distributions and Sale of Fund Shares	0.59%	0.37%	1.81%
Bloomberg Barclays 3-10 Year U.S. Treasury Index (reflects no deduction for fees, expenses or taxes)	1.58%	1.21%	3.69%
Bloomberg Barclays Intermediate U.S. Treasury Index (reflects no deduction for fees, expenses or taxes)	1.14%	0.91%	2.75%

Portfolio Management

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Portfolio Managers

The professionals primarily responsible for the day-to-day management of the Fund are Joanna Madden, Cynthia Moy and Orhan Imer.

Joanna Madden is a Vice President of the Adviser and a Portfolio Manager in the Fixed Income Beta Solutions Group. She joined the Adviser in 2003.

Cynthia Moy is a Principal of the Adviser and a Portfolio Manager in the Fixed Income Beta Solutions Group. She joined the Adviser in 2007.

Orhan Imer, CFA, Ph.D., is a Vice President of the Adviser and a Senior Portfolio Manager in the Fixed Income Beta Solutions Group. He joined the Adviser in 2017.

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Purchase and Sale Information

The Fund will issue (or redeem) Fund Shares to certain institutional investors (typically market makers or other broker-dealers) only in large blocks of 100,000 Fund Shares known as “Creation Units.” Creation Unit transactions are conducted in exchange for the deposit or delivery of a designated portfolio of in-kind securities and/or cash constituting a substantial replication, or a representation, of the securities included in the Fund's benchmark Index.

Individual Fund Shares may only be purchased and sold on the NYSE Arca, Inc., other national securities exchanges, electronic crossing networks and other alternative trading systems through your broker-dealer at market prices. Because Fund Shares trade at market prices rather than at net asset value (“NAV”), Fund Shares may trade at a price greater than NAV (premium) or less than NAV (discount).

Tax Information

The Fund's distributions are expected to be taxed as ordinary income and/or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or individual retirement account. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Fund Shares through a broker-dealer or other financial intermediary (such as a bank), the Adviser or its affiliates may pay the financial intermediary for certain activities related to the Fund, including educational training programs, conferences, the development of technology platforms and reporting systems, or other services related to the sale or promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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